Among viruses, human immunodeficiency virus (hereinafter abbreviated as HIV) that is a type of retrovirus is known to be a cause of acquired immunodeficiency syndrome (hereinafter abbreviated as AIDS). As a therapeutic agent of the AIDS, reverse transcriptase inhibitors (AZT, 3TC, etc.), protease inhibitors (indinavir, etc.), and integrase inhibitors (raltegravir, etc.) are mainly used so far, but problems of side effects such as kidney problems and emergence of resistant viruses have been found, and development of anti-HIV drugs having a mechanism of action different from those is expected.
In addition, in the treatment of AIDS, because resistant viruses easily emerge, it is reported that, multiple drug therapy is currently effective. As the anti-HIV drugs, three types of reverse transcriptase inhibitors, protease inhibitors and integrase inhibitors have been used clinically, but the agents having the same mechanism of action often exhibit cross-resistance, or merely show additive effects, and there is a demand for the development of anti-HIV drugs having a different mechanism of action.
Anti-HIV drugs with a carboxyalkyl type side chain into a six-membered ring nucleus, such as benzene or pyridine, or on their condensed ring, is described in Patent Document 1 to 32 and 36. In particular, five-membered heterocycle condensed with a benzene derivative is described in Patent Document 28 (WO2013/159064), Patent Document 29 (WO2012/145728) etc. Also in Patent Document 16 (WO2012/140243) and Patent Document 36 (WO2014/057103), benzene derivatives having various substituents are described. Moreover anti-HIV drugs having a carboxyalkyl type side chains at 5-membered ring nucleus are described in Patent Document 33 to 35. However, in any of the literature, tricyclic compounds of the present invention are not described.
Furthermore, patents relating to anti-HIV drugs, such as recent integrase inhibitors, have been introduced in Non-patent Document 1.